1. Technical Field
The present invention relates to a recording apparatus that includes a recording head which discharges ultraviolet (UV) ink, which is hardened by irradiation of ultraviolet light, onto a recording material and an ultraviolet light irradiation unit that irradiates ultraviolet light to the discharged UV ink so as to harden the UV ink.
2. Related Art
This type of recording apparatus, that is, a recording apparatus of the past technique equipped with an ultraviolet light irradiation unit that hardens UV ink is disclosed in JP-A-2010-234818.
The recording apparatus described in JP-A-2010-234818 includes a recording head that discharges UV ink onto a recording material and an ultraviolet light irradiation unit that irradiates ultraviolet light to the discharged UV ink so as to harden the UV ink. A metal halide lamp, a light emitting diode (LED), and the like are mentioned therein as an ultraviolet light irradiation unit.
As an ultraviolet light irradiation unit having excellent durability is selected and used from a design viewpoint, it can be said that a risk of failure occurrence is low. However, it is quite difficult to completely prevent the occurrence of a failure.
An ultraviolet light irradiation unit hardly becomes out of order; however, if recording operation is performed by discharging UV ink from a recording head onto a recording material in a state in which the ultraviolet light irradiation unit is out of order, the UV ink will remain unhardened because ultraviolet light is not irradiated to the discharged UV ink. As a result, the recording material and the UV ink will be wasted. In addition, the members forming a recording material transport path, a recording execution region, and the like of a recording apparatus are contaminated by the unhardened UV ink, which may bring about a serious trouble that cannot be settled only by taking out the recording material from the recording apparatus. That is to say, all the contaminated members will have to be decontaminated by cleaning, and the cleaning is expected to be large-scale work including dismantling of the apparatus in general.
In the case where the ultraviolet light irradiation unit has a structure in which a plurality of LEDs are used, if any one of the LEDs becomes out of order, UV ink that corresponds to the failed LED will remain unhardened. Therefore, although UV ink that corresponds to the healthy LEDs other than the failed one is hardened, the recording material that has been recorded on cannot be used as a recorded object, and the problem that the recording material and UV ink are wasted arises as in the case mentioned above. Furthermore, although a range of area contaminated by the unhardened UV ink is relatively small, there exists a problem such that the work to decontaminate the contaminated members by cleaning cannot be avoided.
In the case where the ultraviolet light irradiation unit is configured of, for example, a single metal halide lamp, a user can easily recognize the occurrence of a failure of the lamp. In contrast, in the case where the ultraviolet light irradiation unit has a structure in which a plurality of LEDs are used, if any one of the plurality of LEDs becomes out of order, the user is unlikely to recognize the occurrence of the failure of the LED. Accordingly, in this case, there may exist a large risk such that the aforementioned problems due to the failure will arise.